class_docstr: Mixin for testing batch training.
  
  Inherit this after _TestTraining to enable test cases for batch training.
code: def test_batch_training_cpu_fast(self):
      self._test_batch_training(-1, steps=10, require_success=False)
      self._test_batch_training(
          -1, steps=0, load_model=True, require_success=False
      )
  
imports: import logging
  import os
  import tempfile
  import unittest
  from chainer import testing
  import numpy
  import chainerrl
  from chainerrl.experiments.evaluator import batch_run_evaluation_episodes
  from chainerrl.experiments import train_agent_batch_with_evaluation
  from chainerrl.experiments import train_agent_with_evaluation
  from chainerrl.misc import random_seed
label_desc: Use image node_id 6 for calling the _TestBatchTrainingMixin obj's underlying member method code with example usage: obj.test_batch_training_cpu_fast() without return types